MIG Welding
MIG (Metal Inert Gas) welding is a form of arc welding in which the molten weld pool is protected from oxidisation by a shield of inert gas, such as argon, rather than slag. As with manual metal arc (MMA) welding, the electrode melts to form a weld bead, adding metal to the weld. Unlike MMA welding, the electrode is a continuously fed wire from a spool.
The tip of the welding torch is surrounded by a nozzle, through which the gas is released. The gas also forms a plasma to sustain the arc and channels the weld material from the electrode onto the weld pool.
The term 'MIG' commonly also encompasses MAG (Metal Active Gas) welding which uses CO2 in the shielding gas.
Recent developments from Dinse in MIG welding technology are flat wire welding and 'Cold' MIG welding. Flat wire welding uses a flat ribbon shaped wire, allowing larger weld beads to form on the wire, therefore enabling higher deposition rates to be achieved. 'Cold' MIG welding uses advance wire feed control to periodically reverse the wire which improves droplet transfer, meaning that thin materials can be welded or brazed at lower energy levels.
MIG Advantages
- Weld can be maintained without the constant need to replace the electrode.
- No additional filler material needed to add metal to the weld.
- Ideal for automated robotic welding.
- Less fumes than MMA.
- Cleaner than MMA - no slag to remove from weld.
- Faster than TIG and plasma.
MIG Disadvantages
- Flexibility of wire limits precision in the exact position of the weld.
- Not suitable where no added material is required.
- Relatively low penetration.
- Relatively wide arc means more energy is used, thus higher risk of heat distortion compared to TIG and plasma.
Olympus can supply MIG welding machines, torches and accessories and robot welding systems.